According to the most recent data from the National Diabetes Fact Sheet of the American Diabetes Association, 23.6 million children and adults in the United States are afflicted with diabetes. Each year, 1.6 million new cases of diabetes are diagnosed in people aged 20 years or older. According to a study recently published in the Journal of the American Medical Association, over two-thirds of adults in the United States are either overweight or obese (Flegal et al., JAMA 303(3): 235-241 (2010)) and over one third of this population is obese.
The incretin hormones, glucagon-like peptide-1 (GLP-1) and glucose dependent insulinotropic peptide (GIP), are naturally-occurring peptide hormones. Both GLP-1 and GIP stimulate insulin synthesis and secretion in a glucose-dependent manner and do not produce hypoglycemia (see, e.g., Nauck et al., J. Clin. Endocrinol. Metab. 76:912-917 (1993) and Irwin et al., Regul. Pept. 153:70-76 (2009)).
GLP-1 has been shown to be effective as adjunctive therapy for diabetes and is associated with weight loss. What remains unclear about GIP-targeted therapy, however, is whether successful treatment of diabetes and obesity will be achieved through antagonizing the effects of this hormone (e.g., via GIP receptor antagonism) or through mimicking or enhancing the effects of GIP.